Improvement in locks



waited (t-etre @anni @wird JAMES BRADY, OF BRANFORD, CONNECTICUT,ASSIGi-OR TO THE BRAN- FORD LOCK WORKS, OF SAME PLACE.

Letters Patent No. 103,838, dated June 7, 1870.

IMPROVEMENT IN LOCKS.

The Schedule referred to in these Letters Patent and making part of thesame.

the count-yof New Haven and State of Connecticut,.

have invented a new Improvement in Locks; and I do hereby7 declare thefollowing, when taken in con' nection with the accompanying drawings andthe letters of, reference marked thereon, to be a full, clear, andvexact description of the same, and which said drawings constitute partof this specification, and represent, in

Figure 1, a side view of the plate removed;

Figure 2, the principal key;

Figure 3, the master key;

i Figure 4, the operation with the principal key; and 1n Figure 5, theoperation-with the master key.

This invention relates to an improvement in locks, the object being theconstruction and arrangement of the tuxnblers, so that they may beoperated `by either, one of two difierently-constructed keys, one ofwhich is a master key; and

It consists in constructing one or more of the tumblers with a doublebearing, so that the bit of one key will opemteupon one of the bearings,and the bit of the other key upon the other, both bits raising thetumblers to the same point, `so that the bolt will pass the gate ineither position. v

A Yis the bolt, constructed in the usual manner.

B, one tumbler, pivoted at b, and arranged with a gate, a, throughwhich, when the tumblers are raised, a stud, d, on thebolt, will pass,the tumblers falling down ont-o the stud at either side of the gate,

These -tnmblers maybe more or less in number, and

combined in the usual manner for combining tumblers with the lock-boit.

On the tumblers I form two bearings, I 2, either by rebating thetumbler, or by making a projection thereon, so that the bit of one key.will operate against the edge 1 of the tumbler, and the other 'keyagainst the lprojecting or rabbeted edge 2, as seen in figs. 4 and 5,

that in iig. trepresenting the key as having raised the tumbler, bearingupon the tumbler, and that Ain fig. 5fas the other key, bearing againstthe projection 2. Hence the tumbler is raised to the same point byeither of two different and distinct keys. WVhere several tumblers areemployed, the projections or edges may be varied, but the projection oredge upon which the master key operates should be the same in all thelocks, and the edge upon which the principal key'operates should bedifferent in all such locks,.in order that no two of the-principal keysshall fit the same lock. The variety of keys by such construction, itwill be evident, is almost unlimited.

purpose set forth.

' JAMES BRADY.

Witnesses:

A. J. Tnsnrrs, J. H. SHUMWAY.

